Marathon

Marathon is a first-person shooter developed for the Apple Macintosh by. It was released on December 21, 1994. It is often called a Doom clone, however, it is based on , which came out shortly before Doom. Due to being Mac-only, Marathon was not as popular or well-known as later games such as Duke Nukem 3D, but still had a niche fan base as Doom would not be released for Macs until 1995. All three games in the Marathon series are currently available as freeware for Windows, Linux, and Mac OS X via Aleph One, an enhanced source port.

Marathon is notable for being one of the earliest plot driven first-person shooters, alongside  and Marathon's immediate predecessor Pathways Into Darkness. Most of the story in the game is told through terminals. Although text is a common storytelling medium in recent games, including FPS games, it was revolutionary and abundant in this series for its time, with a strong philosophical bent and a Greek mythology motif (as evidenced in the name of the game itself.)

Marathon coincidentally first released on the same day as fellow Doom rival Rise of the Triad, with which it shares a number of innovations, such as multiplayer-specific maps, the introduction of rocket jumping (later seen in a number of Doom source ports) and the ability to dual wield weapons. The game also received two sequels, Marathon 2: Durandal, first released on November 24, 1995, and Marathon Infinity, first released on October 15, 1996. The two sequels feature a different art style and some other changes, and Marathon 2, unlike the rest of the trilogy, was also officially released for the Microsoft Windows operating system in 1996. Similarly to what happened to the Doom engine in the 90s, Bungie also licensed the Marathon engine to other developers in order for them to create brand new games: these include ', ' and .

Description
Development of the first Marathon game began in late 1993, after the release of Bungie's previous game, , in August of that year. Initially, the game resembled Pathways into Darkness much more closely, and a prototype dated from January 1994 was shown at MacWorld 1994, showcasing a game engine with no verticality, similar to Pathways and Wolfenstein 3D. This drew a negative reception as the release of Doom had made the technology feel obsolete, prompting Bungie to redesign the game from scratch using a more powerful game engine. Marathon was first released to the public in the form of a game demo on November 23, 1994, followed by a full release on December 21, exclusively for Macintosh computers.

In the first Marathon game, the player assumes the role of a cybernetic security officer who is called upon the UESC Marathon, a massive starship colony built out of the Deimos moon. Instead of demons from Hell, the player fights off hordes of vicious aliens known as the Pfhor, while defending panicking crew members and dealing with the ship's artificial intelligences via text terminals. Similar to Doom, the player's starting weapons are a pistol and his fists, and the player faces hazards such as crushing ceilings and lava. The game environment has a similar "2.5D" appearance, with floor, wall, and ceiling textures, actor sprites with eight rotations, elevator lifts, and switches. Notable features included seamless sector-over-sector design, an on-screen motion tracker, free look, swimming through liquids, usage of oxygen tanks in cold vacuum or underwater, and weapons with actual magazines rather than drawing straight from ammo reserves.

Marathon 2: Durandal takes place years after the conclusion of the first game and is set on the alien world of Lh'owon, which is under military occupation by the Pfhor. It features an overhauled art style and all-new sound effects, alongside a new weapon and a slightly modified enemy roster. The third and final entry, Marathon Infinity introduces an element of time travel and features a puzzling storyline open to multiple interpretations. Compared to the second game, it utilizes the same graphics although with all new in-game locations and a new weapon.

Modding
Much like Doom and Doom II, Marathon saw the establishment of a vibrant modding scene over the years, although one that historically remained confined to the Macintosh platform. The first two games did not ship with with any kind of modding tool, but fan-created tools soon appeared, including the Pfhorte map editor in 1995. When Marathon Infinity was released in 1996, however, Bungie bundled in an in-house map editor, Forge, as well as a graphics editor, Anvil. These tools proved immensely popular and quickly made Marathon Infinity the premiere target for most Marathon mods, though some continued to be made for the first two games as well.

Marathon uses somewhat different terminology for its mods, with a multi-level mod typically being referred to as a "scenario", which can include a short levelpack with no new content or also massive total conversions that change most of the graphics, audio and even gameplay of the base game. The term "netmaps" is instead used to refer to multiplayer maps meant for the game's equivalent of Doom's deathmatch. Most mods today are played using the Aleph One source port, which was created following the release of the source code for Marathon 2 by Bungie in January 2000.

For a list of websites covering Marathon mods, see the following:
 * Aleph One's scenarios page, includes a showcase of some of the largest and most popular Marathon mods.
 * Simplici7y, the main filehosting service for Marathon mods and tools, containing many mods, levelpacks and utilities.
 * Citadel, another Aleph One hosted page which contains some conversions of older Marathon mods to newer Aleph One versions.
 * The Pfhorums, containing a section dedicated to mods showcase and discussion.